Method and apparatus for booting hibernation in a portable terminal

ABSTRACT

A method and apparatus for hibernation booting in a mobile terminal supporting two processors are provided. In the hibernation booting method, when power is turned on, a master processor performs hibernation booting. A slave processor performs normal booting under control of the master processor. The master processor and the slave processor determine data needing synchronizing, and perform synchronization depending on whether the data needing synchronizing have been changed.

PRIORITY

This application claims the benefit under 35 U.S.C. §119(a) of a Koreanpatent application filed in the Korean Intellectual Property Office onAug. 27, 2009 and assigned Serial No. 10-2009-0079575, the entiredisclosure of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method and an apparatus for bootinghibernation in a mobile terminal. More particularly, the presentinvention relates to a hibernation booting method and an apparatusthereof in a mobile terminal that supports both an Application Processor(AP) and a Baseband Processor (BP).

2. Description of the Related Art

FIG. 1 illustrates a normal booting procedure of a mobile terminalaccording to the conventional art.

Generally, a mobile terminal performs a booting procedure illustrated inFIG. 1 when power is turned on. Referring to FIG. 1, the mobile terminalexecutes a boot loader in step 101, performs a board initializingprocess of initializing a hardware device in step 103, and performs akernel booting in step 105. The mobile terminal loads a file system tostack the same on Random Access Memory (RAM) in step 107, and loads anapplication to perform initialization in step 109.

Since the above-described booting procedure consumes a lot of time, whena user boots a terminal that performs functions similar to those of aPersonal Computer (PC), for example, a Personal Digital Assistant (PDA)using the above method, the user has to wait and is therebyinconvenienced.

Accordingly, recently, a technique for remarkably reducing a bootingtime by omitting a RAM state setting process (for example, dynamicsymbol resolution, global constructor execution, application specificinitialization and setup, etc.) that consumes most of the time until theterminal becomes ready to be used by the user after a terminal such asthe PDA performs booting, and performing a hibernation technique, isprovided.

The hibernation technique immediately recovers a state where booting iscompleted by temporarily storing job information in a non-volatilememory when power is turned off at a computing system and then omittingan initial booting process and loading the temporarily stored jobinformation when the power is turned on again.

FIG. 2 illustrates a hibernation procedure of a mobile terminalaccording to the conventional art.

As illustrated in FIG. 2, the mobile terminal executes a boot loaderwhen power is turned on in step 201, performs board initialization instep 203, loads information stored in the non-volatile memory, that is,a snapshot image to stack the same in the RAM in step 205, and recoversthe RAM state in step 207.

Recently, a smart phone that supports both a PDA function and a mobilephone function is provided. The smart phone includes an ApplicationProcessor (AP) for supporting the PDA function and a BP for supportingthe mobile phone function. Therefore, the booting process of the smartphone is performed somewhat differently compared with the case ofincluding only one processor. For example, generally, in the smartphone, an AP becomes a master to pass through an initial booting processof the AP, a Baseband Processor (BP) is booted to perform an independentbooting process, and data that need to be shared between the AP and theBP are synchronized. Therefore, it is difficult to apply theconventional hibernation technique that considers only one processor inan apparatus such as the smart phone including two processors.

SUMMARY OF THE INVENTION

An aspect of the present invention is to address at least theabove-mentioned problems and/or disadvantages and to provide at leastthe advantages described below. Accordingly, an aspect of the presentinvention is to provide a method and an apparatus for bootinghibernation in a mobile terminal.

Another aspect of the present invention is to provide a method and anapparatus for booting hibernation in a mobile terminal that supportsboth an Application Processor (AP) and a Baseband Processor (BP).

Still another aspect of the present invention is to provide a method andan apparatus for reducing a synchronization time between an AP and a BPin a mobile terminal that supports both the AP and the BP.

Yet another aspect of the present invention is to provide a method andan apparatus for storing and recovering, by an AP, a snapshot image of aBP in a mobile terminal that supports both the AP and the BP.

Yet still another aspect of the present invention is to provide a methodand an apparatus for performing, by only an AP, hibernation booting, andperforming, by a BP, normal booting in a mobile terminal that supportsboth the AP and the BP.

Yet further another aspect of the present invention is to provide amethod and an apparatus for performing, by both an AP and a BP,hibernation booting in a mobile terminal that supports both the AP andthe BP.

In accordance with an aspect of the present invention, a hibernationbooting method in a mobile terminal that supports two processors isprovided. The method includes when power is turned on, performing, by amaster processor, hibernation booting, performing, by a slave processor,normal booting or hibernation booting under control of the masterprocessor, and determining, by the master processor and the slaveprocessor, data needing synchronizing, and performing synchronizationdepending on whether the data needing synchronizing have been changed.

In accordance with another aspect of the present invention, ahibernation booting apparatus in a mobile terminal that supports twoprocessors is provided. The apparatus includes a master processor forperforming hibernation booting when power is turned on, and a slaveprocessor for performing normal booting or hibernation booting undercontrol of the master processor, wherein the master processor and theslave processor determine data needing synchronizing and performsynchronization depending on whether the data needing synchronizing havebeen changed.

Other aspects, advantages, and salient features of the invention willbecome apparent to those skilled in the art from the following detaileddescription, which, taken in conjunction with the annexed drawings,discloses exemplary embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainexemplary embodiments of the present invention will be more apparentfrom the following description taken in conjunction with theaccompanying drawings in which:

FIG. 1 is a flowchart illustrating a normal booting procedure of amobile terminal according to the conventional art;

FIG. 2 is a flowchart illustrating a hibernation procedure of a mobileterminal according to the conventional art;

FIG. 3 is a block diagram illustrating a mobile terminal according to anexemplary embodiment of the present invention;

FIG. 4 is a block diagram illustrating a mobile terminal according to anexemplary embodiment of the present invention;

FIG. 5 is a diagram illustrating a hibernation performing procedure of amobile terminal where an application processor and a baseband processoruse an independent Random Access Memory (RAM) according to an exemplaryembodiment of the present invention;

FIG. 6 is a diagram illustrating a hibernation performing procedure of amobile terminal where an application processor and a baseband processoruse an independent RAM according to an exemplary embodiment of thepresent invention; and

FIG. 7 is a diagram illustrating a hibernation performing procedure of amobile terminal where an application processor and a baseband processoruse a shared memory according to an exemplary embodiment of the presentinvention.

Throughout the drawings, like reference numerals will be understood torefer to like parts, components, and structures.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of exemplaryembodiments of the invention as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the embodiments described hereincan be made without departing from the scope and spirit of theinvention. Also, descriptions of well-known functions and constructionsare omitted for clarity and conciseness.

The terms and words used in the following description and claims are notlimited to the bibliographical meanings, but, are merely used by theinventor to enable a clear and consistent understanding of theinvention. Accordingly, it should be apparent to those skilled in theart that the following description of exemplary embodiments of thepresent invention are provided for illustration purpose only and not forthe purpose of limiting the invention as defined by the appended claimsand their equivalents.

It is to be understood that the singular forms “a,” “an,” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, reference to “a component surface” includes referenceto one or more of such surfaces.

Exemplary embodiments of the present invention provide a hibernationbooting method and an apparatus thereof in a mobile terminal thatsupports both an Application Processor (AP) and a Baseband Processor(BP). Here, the mobile terminal denotes a terminal that supports both anapplication function for managing user data and data such as music andmoving images, and a mobile phone function. In the followingdescription, a terminal that supports a Personal Digital Assistant (PDA)function and a mobile phone function is exemplarily described. Inaddition, though an exemplary embodiment of the present invention isdescribed using the case where the AP operates as a master, it isapplicable to the case where the BP operates as a master.

FIG. 3 is a block diagram illustrating a mobile terminal according to anexemplary embodiment of the present invention.

Referring to FIG. 3, the mobile terminal includes a first processor (forexample, a Central Processing Unit (CPU)) 300, a second processor 310, afirst Random Access Memory (RAM) 304, a second RAM 312, a flash memory302, and a Dual Port RAM (DPRAM) 306. Here, a description is made usingan example where the first processor 300 supports a PDA function, andthe second processor 310 supports a mobile phone function. That is, thedescription is made on the assumption that the first processor serves asan AP, and the second processor 310 serves as a BP.

The first processor 300 controls and processes overall operations forthe PDA function, controls a snapshot image representing job informationto be temporarily stored in the flash memory 302 when power is turnedoff, and controls the snapshot image stored in the flash memory 302 tobe stacked in the first RAM 304 or the second RAM 312 when the power isturned on. At this point, only the first processor 300 may perform thehibernation booting and the second processor 310 may perform the normalbooting, or both the first and second processors 300 and 310 may performthe hibernation booting.

In the case where only the first processor 300 performs the hibernationbooting, the first processor 300 executes a boot loader and initializesa board, loads a snapshot image of an application from the flash memory302 to stack the snapshot image on the first RAM 304 and recover thestate of the first RAM 304, outputs a power-on-signal so that the secondprocessor 310 may perform a booting process, and controls and processesto perform synchronization with the second processor 310 that hasperformed the normal booting. At this point, the first processor 300 andthe second processor 310 determines the minimum data that needs to besynchronized based on data stored in the first RAM 304 and data storedin the second RAM 312 to perform synchronization on only data havingdifferent values. This is because data subject to the second processor310 exist among data stored in the first RAM 304 used by the firstprocessor 300. For example, when a Subscriber Identification Module(SIM) card (not shown) has not been changed after the booting, Real TimeClock (RTC), Public Land Mobile Network (PLMN), Service Principal Name(SPN), a battery level, a Received Signal Strength Indicator (RSSI)level, a network state, and a system IDentifier (ID) are synchronized,and SIM card-related data (for example, phonebook data and message data)are not synchronized. In contrast, when the SIM card has been changedafter the booting, RTC, PLMN, SPN, a battery level, an RSSI level, anetwork state, and a system ID are synchronized, and the SIMcard-related data are also synchronized. Here, the second processor 310may determine whether the SIM card has been changed. The secondprocessor 310 may determine whether the SIM card has been changedthrough an Integrated Circuit Card IDentity (ICCID) of the SIM card.

In the case where both the first processor 300 and the second processor310 perform the hibernation booting, the first processor 300 executes aboot loader and initializes a board, and loads a snapshot image of anapplication from the flash memory 302 to stack the snapshot image on thefirst RAM 304 and recover the state of the first RAM 304. After that,the first processor 300 outputs a power-on-signal so that the secondprocessor 310 may perform the booting process, and loads a snapshotimage of a baseband from the flash memory 302 to stack the same in theDPRAM 306. After that, the first processor 300 controls and processes toperform synchronization with the second processor 310 that has performedhibernation booting. At this point, the synchronization process isperformed in the same way as only the first processor 300 performs thehibernation booting.

The second processor 310 controls and processes overall operations ofthe mobile phone function. When a power-on-signal is provided from thefirst processor 300, the second processor 310 performs the normalbooting or the hibernation booting. During the normal booting, thesecond processor 310 performs booting according to a procedure shown inFIG. 1, determines whether data have been changed after the booting, andperforms synchronization only when the data have been changed. This isbecause snapshot images of the first and second processors 300 and 310have been generated at the same point, so that synchronization dataincluded in the snapshot image are the same.

During the hibernation booting, the second processor 310 initializes aboard, that is, a modem unit, loads the snapshot image of the basebandfrom the DPRAM 306 to stack the same on the second RAM 312, determineswhether data have been changed after the booting, determines the minimumdata to be synchronized with that of the first processor 300, andperforms synchronization on only data having different values.

The first RAM 304 and the second RAM 312 are memories subject to thefirst processor 300 and the second processor 310, respectively, andstack corresponding snapshot images to immediately recover abooting-completed state.

The flash memory 302 is a non-volatile memory maintaining stored dataeven when power is turned off, and stores the snapshot image of theapplication or the snapshot image of the baseband.

The DPRAM 306 is accessible by both the first processor 300 and thesecond processor 310, and more particularly, is used for the firstprocessor 300 to transfer the snapshot image of the baseband to thesecond processor 310 according to an exemplary embodiment of the presentinvention.

FIG. 4 is a block diagram illustrating a mobile terminal according to anexemplary embodiment of the present invention.

Referring to FIG. 4, the mobile terminal includes a first processor 400(for example, a CPU), a second processor 410, a flash memory 402, and aOneDRAM 404. Here, a description is made using an example where thefirst processor 400 supports a PDA function, and the second processor410 supports a mobile phone function. That is, the description is madeon the assumption that the first processor 400 serves as an AP, and thesecond processor 410 serves as a BP.

The first processor 400 controls and processes overall operations forthe PDA function, controls a snapshot image representing job informationto be temporarily stored in the flash memory 402 when power is turnedoff, and controls the snapshot image stored in the flash memory 402 tobe stacked in the OneDRAM 404 when the power is turned on. At thispoint, only the first processor 400 may perform the hibernation bootingand the second processor 410 may perform the normal booting, or both thefirst and second processors 400 and 410 may perform the hibernationbooting. Since overall operations of the first processor 400 is the sameas that of the first processor 300 of FIG. 3, description thereof isomitted. The first processor 300 of FIG. 3 stacks a snapshot image of anapplication on the first RAM, and transfers a snapshot image of thebaseband to the second processor 310 through the DPRAM 306, but thefirst processor 400 of FIG. 4 stacks snapshot images of the applicationand the baseband loaded from the flash memory 402 in the OneDRAM 404.

The second processor 410 controls and processes an overall function forthe mobile phone function. Here, since overall operations of the secondprocessor 410 are the same as that of the second processor 310 of FIG.3, a description thereof is omitted. The second processor 310 of FIG. 3loads a snapshot image of the baseband from the DPRAM 306 to stack thesame on the second RAM 312, but the second processor 410 of FIG. 4 loadsa snapshot image of the baseband from a shared region of the OneDRAM 404to stack the same on a region of the OneDRAM 404, that is used by thesecond processor 410.

The OneDRAM 404 is obtained by merging two kinds of DRAMs havingdifferent functions, or merging SRAM and DRAM into one. The OneDRAM 404is a shared memory of the first processor 400 and the second processor410. The OneDRAM 404 includes one memory physically, but is divided intoa memory region subject to the first processor 400 and the secondprocessor 410, and a memory region shared by the two processorslogically.

The flash memory 402 is a non-volatile memory maintaining stored dataeven when power is turned off, and stores a snapshot image of anapplication or a snapshot image of a baseband.

FIG. 5 is a diagram illustrating a hibernation performing procedure of amobile terminal where an AP and a BP use independent RAMs, respectively,according to an exemplary embodiment of the present invention. That is,a case where an AP 500 performs hibernation booting and a BP 502performs normal booting in the mobile terminal having the structureillustrated in FIG. 3 is described.

Referring to FIG. 5, when power is turned on, the AP 500 executes a bootloader in step 510, and initializes a board in step 512. The AP 500loads a snapshot image of an application from the flash memory 302 tostack the same on the first RAM 304 used by the AP in step 514, andrecovers a RAM state in step 516.

The AP 500 transmits a power-on-signal to the BP 502 in step 518.

The BP 502 that receives the power-on-signal performs normal booting instep 520, determines whether a SIM card has been changed after thebooting in step 522, and informs the AP 500 that whether the SIM cardhas been changed in step 524. At this point, whether the SIM card hasbeen changed is determined by comparing ICCIDs before and after thebooting. Here, the ICCID before the booting is included in the snapshotimage of the application and may be provided by the AP 500.

The AP 500 and the BP 502 perform a synchronization process depending onwhether the SIM card has been changed in step 526. For example, when theSIM card has not been changed, RTC, PLMN, SPN, a battery level, a RSSIlevel, a network state, and a system ID are synchronized, and SIMcard-related data is not synchronized. In contrast, when the SIM cardhas been changed, RTC, PLMN, SPN, a battery level, an RSSI level, anetwork state, and a system ID are synchronized, and the SIMcard-related data is also synchronized. Here, the network state denotesone of a no service state (NoSVC), an urgent state, and a normalregistration state of the terminal. The system ID denotes one ID of GSM,GPRS, EDGE, WCDMA, and HSDPA.

FIG. 6 is a diagram illustrating a hibernation performing procedure of amobile terminal where an AP and a BP use independent RAMs, respectively,according to an exemplary embodiment of the present invention. That is,a case where an AP 600 and a BP 602 perform hibernation booting in themobile terminal having the structure illustrated in FIG. 3 is described.

Referring to FIG. 6, when power is turned on, the AP 600 executes a bootloader in step 610 and initializes a board in step 612. The AP 600 loadsa snapshot image of an application from the flash memory 302 to stackthe same in the first RAM 304 used by the AP 600 in step 614, andrecovers a RAM state in step 616.

The AP 600 transmits a power-on-signal to the BP 602 in step 618, andloads a snapshot image of the baseband from the flash memory 302 totransmit the same to the BP 602 through the DPRAM 306 in step 620. Thatis, the AP 600 loads the snapshot image of the baseband to record thesame on the DPRAM 306 accessible by the BP 602.

The BP 602 initializes a board in step 622 and stacks the snapshot imageof the baseband received from the AP 600 via the DPRAM 306 on the secondRAM 312 used by the BP in step 624. That is, the BP 602 loads thesnapshot image of the baseband from the DPRAM 306 to stack the same onthe second RAM 312. The BP 602 determines whether a SIM card has beenchanged after the booting in step 626, and informs the AP 600 thatwhether the SIM card has been changed in step 628. At this point,whether the SIM card has been changed is determined by comparing ICCIDsbefore and after the booting. Here, the ICCID before the booting isincluded in the snapshot image of the application and may be provided bythe AP 600.

The AP 600 and the BP 602 perform a synchronization process depending onwhether the SIM card has been changed in step 630. Here, the AP 600 andthe BP 602 do not perform a separate synchronization process when theSIM card has not been changed, and perform the synchronization processon the SIM card-related data when the SIM card has been changed. This isbecause snapshot images of the AP 600 and the BP 602 have been generatedat the same point, so that synchronization data included in the snapshotimages are the same.

The BP 602 completes the booting process by recovering a state of thesecond RAM 312 in step 632.

FIG. 7 is a diagram illustrating a hibernation performing procedure of amobile terminal where an AP and a BP use a shared memory according to anexemplary embodiment of the present invention. That is, a case where anAP and a BP perform hibernation booting in the mobile terminal havingthe structure illustrated in FIG. 4 is described.

Referring to FIG. 7, when power is turned on, an AP 700 executes a bootloader in step 710 and initializes a board in step 712. The AP 700 loadsa snapshot image of an application from the flash memory 402 to stackthe loaded snapshot image in a memory region of the OneDRAM 404, whichis used by the AP 700 in step 714. The OneDRAM 404 is shared by the AP700 and the BP 702. The AP 700 recovers a state of the region of theOneDRAM, which is used by the AP 700 in step 716.

The AP 700 transmits a power-on-signal to the BP 702 in step 718 andloads a snapshot image of the baseband from the flash memory 402 torecord the same in the shared memory in step 720. That is, the AP 700records the snapshot image of the baseband in the memory region of theOneDRAM 404, which is shared by the AP 700 and the BP 702.

The BP 702 that receives the power-on-signal initializes a board in step722 and loads a snapshot image of the baseband from the shared memory tostack the same on the memory region of the OneDRAM 404, which is used bythe BP in step 724. The BP 702 determines whether a SIM card has beenchanged after the booting in step 726 and informs the AP 700 whether theSIM card has been changed in step 728. At this point, whether the SIMcard has been changed is determined by comparing ICCIDs before and afterthe booting. Here, the ICCID before the booting is included in thesnapshot image of the application and may be provided by the AP 700.

The AP 700 and the BP 702 perform a synchronization process depending onwhether the SIM card has been changed in step 730. Here, the AP 700 andthe BP 702 do not perform a separate synchronization process when theSIM card has not been changed, and perform the synchronization processon the SIM card-related data when the SIM card has been changed. This isbecause snapshot images of the AP 700 and the BP 702 have been generatedat the same point, so that synchronization data included in the snapshotimages are the same.

The BP 702 completes the booting process by recovering a state of theregion of the OneDRAM 404, which is used by the BP 702 in step 732.

Here, since the AP 700 and the BP 702 share the memory, the AP 702 maydirectly stack the snapshot image of the baseband on the shared regionof the memory. In this case, the AP 700 may play a leading role forrecovering the RAM state.

Though both the AP and the BP perform hibernation booting in the casewhere the AP and the BP use the shared memory in the above description,only the AP may perform the hibernation booting and the BP may performthe normal booting in the case where the shard memory is used. At thispoint, operations of the AP and the BP are similar to those illustratedin FIG. 5 on the whole, and only a memory using method may be different.

In addition, though the BP determines whether the data forsynchronization between the processors have been changed in the abovedescription, the AP may receive related data from the BP to determinewhether the data have been changed.

According to an exemplary embodiment of the present invention, a mobileterminal that supports both an AP and a BP guarantees a fast bootingtime by performing hibernation booting for the AP and the BP to controldata to be synchronized depending on data change, and reducing a timedelay caused by a booting process.

While the invention has been shown and described with reference tocertain exemplary embodiments thereof, it will be understood by thoseskilled in the art that various changes in form and details may be madetherein without departing from the spirit and scope of the invention asdefined by the appended claims and their equivalents.

What is claimed is:
 1. A hibernation booting method in a mobile terminalthat supports two processors, the method comprising: when power isturned on, performing, by a master processor, hibernation booting;performing, by a slave processor, normal booting or hibernation bootingunder control of the master processor; and determining, by the masterprocessor and the slave processor, data needing synchronizing, andperforming synchronization depending on whether the data needingsynchronizing have been changed.
 2. The method of claim 1, wherein themaster processor and the slave processor use independent memories,respectively, or use a shared memory.
 3. The method of claim 1, whereinif it is determined that the data have not been changed, the dataneeding synchronizing are determined such that the data comprise atleast one of Real Time Clock (RTC), Public Land Mobile Network (PLMN),Service Principal Name (SPN), a battery level, a Received SignalStrength Indicator (RSSI) level, a network state, and a systemIDentifier (ID).
 4. The method of claim 1, wherein if it is determinedthat the data have been changed, the data needing synchronizing aredetermined such that the data comprise at least one of Real Time Clock(RTC), Public Land Mobile Network (PLMN), Service Principal Name (SPN),a battery level, a Received Signal Strength Indicator (RSSI) level, anetwork state, a system IDentifier (ID), and the changed data.
 5. Themethod of claim 1, wherein the determining of whether the data needingsynchronizing have been changed comprises comparing Integrated CircuitCard IDentities (ICCIDs) of a Subscriber Identification Module (SIM)card before and after the booting.
 6. The method of claim 5, wherein theICCID of the SIM card before the booting is included in a snapshot imagefor hibernation of the master processor.
 7. The method of claim 1,wherein the performing of, by the slave processor, the hibernationbooting under control of the master processor comprises loading, by themaster processor, a snapshot image of the slave processor from anon-volatile memory to provide the loaded snapshot image to the slaveprocessor.
 8. The method of claim 1, wherein the performing, by theslave processor, of the hibernation booting comprises: when the twoprocessors use independent memories, respectively, providing, by themaster processor, a snapshot image of the slave processor via a linkbetween the two processors; and stacking, by the slave processor, thesnapshot image of the slave processor in the memory of the slaveprocessor.
 9. The method of claim 1, wherein the performing, by theslave processor, of the hibernation booting comprises: when the twoprocessors use a shared memory, recording, by the master processor, asnapshot image of the slave processor in a shared region of the sharedmemory; and stacking, by the slave processor, the snapshot image of theslave processor in a region of the shared memory that is used by theslave processor.
 10. The method of claim 1, further comprising: when thedata have not been changed, not performing the synchronization; and whenthe data have been changed, performing the synchronization on thechanged data.
 11. A hibernation booting apparatus in a mobile terminalthat supports two processors, the apparatus comprising: a masterprocessor for performing hibernation booting when power is turned on;and a slave processor for performing normal booting or hibernationbooting under control of the master processor, wherein the masterprocessor and the slave processor determine data needing synchronizingand perform synchronization depending on whether the data needingsynchronizing have been changed.
 12. The apparatus of claim 11, furthercomprising: first and second memories corresponding to the masterprocessor and the slave processor, respectively; or a third memoryshared by the master processor and the slave processor.
 13. Theapparatus of claim 11, wherein if it is determined that the data havenot been changed, the master processor and the slave processor determinethe data needing synchronizing such that the data comprise at least oneof Real Time Clock (RTC), Public Land Mobile Network (PLMN), ServicePrincipal Name (SPN), a battery level, a Received Signal StrengthIndicator (RSSI) level, a network state, and a system IDentifier (ID).14. The apparatus of claim 11, wherein if it is determined that the datahave been changed, the master processor and the slave processordetermine the data needing synchronizing such that the data comprise atleast one of Real Time Clock (RTC), Public Land Mobile Network (PLMN),Service Principal Name (SPN), a battery level, a Received SignalStrength Indicator (RSSI) level, a network state, a system IDentifier(ID), and the changed data.
 15. The apparatus of claim 11, wherein themaster processor and the slave processor compare Integrated Circuit CardIDentities (ICCIDs) of a Subscriber Identification Module (SIM) cardbefore and after the booting to determine if the data needingsynchronizing have been changed.
 16. The apparatus of claim 11, furthercomprising a non-volatile memory for storing a snapshot image forhibernation of the master processor, wherein the snapshot imagecomprises ICCID information of a SIM card before the booting.
 17. Theapparatus of claim 11, further comprising a non-volatile memory forstoring snapshot images of the master processor and the slave processor,wherein the master processor loads the snapshot image of the slaveprocessor from the non-volatile memory to provide the loaded snapshotimage to the slave processor.
 18. The apparatus of claim 11, whereinwhen the two processors use independent memories, respectively, themaster processor provides a snapshot image of the slave processor via alink between the two processors, and the slave processor stacks thesnapshot image of the slave processor provided via the link in thememory of the slave processor.
 19. The apparatus of claim 11, whereinwhen the two processors use a shared memory, the master processorrecords a snapshot image of the slave processor in a shared region ofthe shared memory, and the slave processor stacks the snapshot image ofthe slave processor in a region of the shared memory, which is used bythe slave processor.
 20. The apparatus of claim 11, wherein the masterprocessor and the slave processor do not perform synchronization whenthe data have not been changed, and perform the synchronization on thechanged data when the data have been changed.